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Design and synthesis of selective manganese(II) chelators
Míka, Luděk ; Kotek, Jan (advisor) ; Tauchman, Jiří (referee)
Title: Design and synthesis of selective manganese(II) chelators Autor: Luděk Míka Department: Department of Inorganic Chemistry, Faculty of Science Supervisor: doc. RNDr. Jan Kotek, Ph.D. Supervisor's e-mail address: modrej@natur.cuni.cz Abstract:Abstract:Abstract:Abstract: The aim of this project is to synthetize new kind of macrobicyclic ligands derived from cross-bridged cyclam for complexation of Mn2+ ions. These complexes may be potentially used as contrast agents in magnetic resonance imaging. Three macrobicyclic ligand with various pendant arms were synthesized. The ability to complex manganese(II) ions were studied by Mass Spectroscopy. Electrochemical properties of manganese(II) complexes with general chelating agents and one synthesized ligand were studied using cyclic voltammetry. Keywords:Keywords:Keywords:Keywords: cross-bridged cyclam, phosphonate, phosphinate, pendant arms, manganese
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Phosphinoferrocene amides with glycine pendant groups
Tauchman, Jiří
The reaction of 1′-(diphenylphosphino)-1-ferrocenecarboxylic acid (Hdpf) with H2NCH2CO2CR3 mediated by peptide coupling agents (EDC/HOBt) afforded novel glycine phosphino-carboxamides Ph2PfcCONHCH2CO2CR3 (fc = ferrocene-1,1′-diyl; R = H (2) and Me (3*)). Compound 2 was converted to its corresponding phosphine oxide (5*) and sulfide (6*), to N-acyl glycine Ph2PfcCONHCH2CO2H (7), and to bis-amide Ph2PfcCONHCH2CONH2 (8*). Compounds 2 and 8 reacted with [PdCl2(cod)] (cod = η2 :η2 - cycloocta-1,5-diene) and 7 reacted with Na2[PdCl4] to afford the respective, mostly solvated bis-phosphine complexes trans-[PdCl2(L-κP)2] (9: L = 2; 10: L = 7, 11: L = 8). Furthermore, bridge cleavage reaction of [{Pd(μ-Cl)(LNC )}2] (LNC = 2-[(dimethylamino-κN)methyl]phenyl- κC1 ) (12) with 2 gave [(LNC )Pd(Cl)(2-κP)] (13*), which was further reacted with AgClO4 or KOt-Bu to afford bis-chelate complexes [(LNC )Pd(2-κ2 O,P)]ClO4 (14*) and [(LNC )Pd(L- κ2 N,P)] (15*; L = 2 deprotonated at the NH group), respectively. All compounds were characterized by spectroscopic methods (multinuclear NMR, MS, and IR) and by elemental analyses; the asterisk indicates that the crystal structure has been determined. Phosphine 7 in combination with palladium(II) acetate were shown to be highly active catalysts for the Suzuki-Miyaura cross-coupling of...
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Phosphinoferrocene conjugates of selected amino acids
Tauchman, Jiří ; Štěpnička, Petr (advisor) ; Růžička, Aleš (referee) ; Dvořák, Dalimil (referee)
A series of chiral phosphinoferrocene amides was prepared by the condensation either of 1'- (diphenylphosphino)ferrocene-1-carboxylic acid (Hdpf) or its planar-chiral 1,2-isomers and amino acid methyl esters in the presence of peptide coupling agents. The resulting phosphinoamides were tested as ligands in Cu-catalyzed asymmetric conjugate additions of diethylzinc to chalcones and in Pd-mediated asymmetric allylic substitution reactions of 1,3- diphenylallyl acetate with the respective nucleophile (alkylation, amination and etherification). The catalytic tests were focused on an optimization of the reaction parameters (solvent, temperature, base, metal/ligand ratio) and on survey of various substrates. Compounds based on Hdpf proved to be better ligands in both catalytic reactions than their planar chiral analogues. In order to rationalize the influence of the ligand structure on the reaction course and also to interpret the catalytic results, several model complexes were prepared and structurally characterized. Other three series of non-chiral complexes were prepared from the corresponding (η6 - arene)ruthenium(II) precursor and Hdpf-glycine conjugates; the neutral complexes of the type [(arene)RuCl2(Hdpf-Gly(R)-κP)] (arene = benzene, p-cymene, hexamethyl-benzene; R = OMe, NH2, OH) as well as two...
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Design and synthesis of selective manganese(II) chelators
Míka, Luděk ; Kotek, Jan (advisor) ; Tauchman, Jiří (referee)
Title: Design and synthesis of selective manganese(II) chelators Autor: Luděk Míka Department: Department of Inorganic Chemistry, Faculty of Science Supervisor: doc. RNDr. Jan Kotek, Ph.D. Supervisor's e-mail address: modrej@natur.cuni.cz Abstract:Abstract:Abstract:Abstract: The aim of this project is to synthetize new kind of macrobicyclic ligands derived from cross-bridged cyclam for complexation of Mn2+ ions. These complexes may be potentially used as contrast agents in magnetic resonance imaging. Three macrobicyclic ligand with various pendant arms were synthesized. The ability to complex manganese(II) ions were studied by Mass Spectroscopy. Electrochemical properties of manganese(II) complexes with general chelating agents and one synthesized ligand were studied using cyclic voltammetry. Keywords:Keywords:Keywords:Keywords: cross-bridged cyclam, phosphonate, phosphinate, pendant arms, manganese
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Phosphinoferrocene amides with glycine pendant groups
Tauchman, Jiří
The reaction of 1′-(diphenylphosphino)-1-ferrocenecarboxylic acid (Hdpf) with H2NCH2CO2CR3 mediated by peptide coupling agents (EDC/HOBt) afforded novel glycine phosphino-carboxamides Ph2PfcCONHCH2CO2CR3 (fc = ferrocene-1,1′-diyl; R = H (2) and Me (3*)). Compound 2 was converted to its corresponding phosphine oxide (5*) and sulfide (6*), to N-acyl glycine Ph2PfcCONHCH2CO2H (7), and to bis-amide Ph2PfcCONHCH2CONH2 (8*). Compounds 2 and 8 reacted with [PdCl2(cod)] (cod = η2 :η2 - cycloocta-1,5-diene) and 7 reacted with Na2[PdCl4] to afford the respective, mostly solvated bis-phosphine complexes trans-[PdCl2(L-κP)2] (9: L = 2; 10: L = 7, 11: L = 8). Furthermore, bridge cleavage reaction of [{Pd(μ-Cl)(LNC )}2] (LNC = 2-[(dimethylamino-κN)methyl]phenyl- κC1 ) (12) with 2 gave [(LNC )Pd(Cl)(2-κP)] (13*), which was further reacted with AgClO4 or KOt-Bu to afford bis-chelate complexes [(LNC )Pd(2-κ2 O,P)]ClO4 (14*) and [(LNC )Pd(L- κ2 N,P)] (15*; L = 2 deprotonated at the NH group), respectively. All compounds were characterized by spectroscopic methods (multinuclear NMR, MS, and IR) and by elemental analyses; the asterisk indicates that the crystal structure has been determined. Phosphine 7 in combination with palladium(II) acetate were shown to be highly active catalysts for the Suzuki-Miyaura cross-coupling of...
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